Nectar feeder access devices

ABSTRACT

A device for use on various nectar-type bird feeders, that prevents insect contamination. The device presents an effective physical barrier to the entry of insects, but is easily penetrated by the bill of a feeding bird. The device can be constructed to fit any of the currently available nectar feeder configurations or may be incorporated into feeders, specially adapted.

This application is a continuation-in-part of Ser. No. 435,537 filed May5, 1995, now U.S. Pat. No. 5,640,927.

FIELD OF THE INVENTION

The present invention relates to access devices for bird feeders andfeeders incorporating such devices. More specifically, the presentinvention relates to feeder access devices that act to restrict insectsfrom feeding at and/or contaminating nectar type bird feeders.

BACKGROUND OF THE INVENTION

Insect feeding and contamination of nectar feeders is a familiar problemand numerous attempts have been made to deter insects from feeding andcontaminating nectar feeders. The most frequently used approach is touse a liquid filled moat to prevent crawling insects from reaching thefeeder. These moats are either hung interposed as in "Insect Trap for aBird Feeder" of Hiday, U.S. Pat. No. 4,980,990, or incorporated as aportion of the feeder as in "Hummingbird Feeder" of Queen, U.S. Pat. No.3,301,220. These moat designs require regular refilling, unpleasantcleaning, and do not protect the feeder from flying insects. Bee and antguards are incorporated in the "Hummingbird Feeding Device" of FowlerU.S. Pat. No. 3,125,069.

Although not related to nectar feeders, U.S. Pat. No. 3,558,022 to Zytkoet al. discloses a "Container Safety Closure" that is penetrated with adispensing dropper. The structure of this device is unsuitable for usein protecting nectar feeders from contamination for a number of reasons:First, the device is intended to form a tight hermetic seal. As such, itwould require a relatively high displacement force to allow for thepenetration of a bird's bill. Second, along with this high displacementforce, and due to the high frictional coefficient of resilientmaterials, there would be a large frictional resistance to thepenetration and withdrawal of a bird's bill. Third, the structure of thedevice would serve to trap insects at its lowest point, once there, theywould have a high probability of being introduced into the feeder by apenetrating bill. Finally, the structure of the device does not lenditself to installation on any known nectar feeder type.

Whatever precise merits, features, and advantages of the above citedreferences, none of them achieves or fulfills the purpose of the nectarfeeder access device of the present invention.

The principal object of the present invention is to provide simpledevices to be installed on nectar feeders which will permit easypenetration of the bird's bill, while restricting the entry of anyinsect life. It is also the object of the present invention to providesuch devices as can be readily installed on many of the popular nectarfeeder configurations. A further object is to provide devices that canbe integrated into a new design of nectar feeder, which are simple,reliable, and inexpensive to manufacture.

SUMMARY OF THE INVENTION

A restrictive access device constructed to allow for secure attachmentin or over the feeder opening in the body of a nectar-type bird feeder.The restrictive access device having an incorporated structure thatpresents a physical barrier to insect entry at the feeder opening. Theinsect barrier portion of the device consisting of a normally closedpassageway that is adapted to be readily opened when pushed orpenetrated by a bird's bill. This passageway is biased to return to thenormally closed position when the bird's bill is withdrawn.

Other and further objects of the present invention will be apparent fromthe following description and claims, and are illustrated in theaccompanying drawings, which by way of illustration, show a series ofembodiments of the present invention and the principles thereof, andwhat is now considered to be the best mode in which to apply theseprinciples. Other and different embodiments of the invention embodyingthe same or equivalent principles may be used and structural changes maybe made as desired by those skilled in the art without departing fromthe invention.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 depicts a side cross sectional view of a tubular shaped barrierinsert for the restrictive access device of the invention;

FIG. 2 depicts a side cross sectional view of the resilient housingadapted to hold the barrier insert of FIG. 1;

FIG. 3 depicts a top view of the assembled restrictive access device ofFIG. 1 and FIG. 2;

FIG. 4 depicts a side cross sectional view of the restrictive accessdevice of FIG. 3 being penetrated by a bird's bill;

FIG. 5 depicts a side cross sectional view of an alternate restrictiveaccess device that incorporates a flap type barrier insert;

FIG. 6 depicts a top view of the restrictive access device of FIG. 5;

FIG. 7 depicts a side cross sectional view of the flap type barrierinsert of the restrictive access device of FIG. 5;

FIG. 8 depicts a side cross sectional view of the resilient housing ofthe restrictive access device of FIG. 5;

FIG. 9 depicts a side cross sectional view of the restrictive accessdevice of FIG. 5 being penetrated by a bird's bill;

FIG. 10 depicts, on a different scale, a side cross sectional view ofthe restrictive access device of FIG. 5 configured to fit in place of aconventional bee guard;

FIG. 11 depicts a side cross sectional view of a conventionalhummingbird feeder flower cup;

FIG. 12 depicts a top view of the restrictive access device of FIG. 10and the conventional hummingbird feeder flower cup of FIG. 11 assembled;

FIG. 13 depicts, on a different scale, a side cross sectional view ofthe restrictive access device of FIG. 5 configured to fit an invertedtype tube feeder;

FIG. 14 depicts an enlarged view of the check valve (in its closedposition) of the device of FIG. 13;

FIG. 15 depicts an enlarged view of the check valve (in its openposition) of the device of FIG. 13;

FIG. 16 depicts a frontal view of the device of FIG. 13;

FIG. 17 depicts a top view of a two piece restrictive access device witha removable flap type barrier;

FIG. 18 depicts a side cross sectional and exploded view of thecomponent parts of the device of FIG. 17;

FIG. 18A depicts a top view of the removable flap type barrier of FIG.18;

FIG. 19 depicts a side cross sectional view of the device of FIG. 17;

FIG. 20 depicts the restrictive access device of FIGS. 17, 18 and 19being penetrated by a bird's bill;

FIG. 21 depicts a top view of an integrally constructed, flap typebarrier access device;

FIG. 22 depicts a side cross sectional view of the restrictive accessdevice of FIG. 21;

FIG. 23 depicts a side cross sectional view of the device of FIG. 21being penetrated by a bird's bill;

FIG. 24 depicts a top view of an integrally constructed, bristle orfilament type barrier restrictive access device;

FIG. 25 depicts, on an enlarged scale, a side cross sectional view ofthe device of FIG. 24;

FIG. 26 depicts a top view of a two piece, bristle or filament typebarrier restrictive access device;

FIG. 26A depicts the bristle or filament type barrier insert of thedevice of FIG. 26;

FIG. 27 depicts a side cross sectional view of the device of FIG. 26;

FIG. 28 depicts the device of FIGS. 26 and 27 being penetrated by abird's bill;

FIG. 29 depicts a top view of a unitary construction bristle or filamenttype barrier, restricted access device of the invention;

FIG. 30 depicts a side cross sectional view of the device of FIG. 29;

FIG. 31 depicts a top view of a unitarily constructed, fluted typebarrier restrictive access device of the present invention;

FIG. 31A depicts a top view of a fluted type barrier structure of thetype illustrated in FIG. 31, having a triple flute closure;

FIG. 31B depicts a top view of a fluted type barrier structure of thetype illustrated in FIG. 31, having a single flute closure;

FIG. 32 depicts a side cross sectional view of the device of FIG. 31;

FIG. 33 depicts a side cross sectional view of the device of FIG. 31being penetrated by a bird's bill;

FIG. 34 depicts a side cross sectional view of a two piece, webbed typebarrier restrictive access device of the present invention;

FIG. 34A depicts a top view of the webbed barrier structure of thedevice of FIG. 34;

FIG. 34B depicts a top view of the closure band of the device of FIG.34;

FIG. 35 depicts the device of FIG. 34 being penetrated by a bird's bill;

FIG. 35A depicts a top view of the webbed barrier structure of thedevice in the position illustrated in FIG. 35;

FIG. 35B depicts a top view of the closure band of the device in theposition illustrated in FIG. 35;

FIG. 36 depicts a top view of an adhesively attached constructionversion of the restrictive access device of the present invention;

FIG. 37 depicts a side cross sectional view of the device of FIG. 36;

FIG. 38 depicts a top view of a gravitationally biased barrierrestrictive access device of the invention;

FIG. 39 depicts a side, partial cross sectional view of the device ofFIG. 38;

FIG. 39B depicts a one quarter rotation of the view of FIG. 39;

FIG. 40 depicts the device of FIG. 39 being penetrated by a bird's bill;

FIG. 41 depicts a frontal view of an unitarily constructed, invertedfeeder construction restrictive access device of the invention;

FIG. 42 depicts a side cross sectional view of the device of FIG. 41;

FIG. 43 depicts a top view of a saucer type nectar feeder with therestrictive access barrier incorporated integrally within the feedertop;

FIG. 44 depicts a side cross sectional view of the device of FIG. 43,taken along lines 44--44;

FIG. 44A depicts an enlarged view of the annular restrictive accessbarrier portion of FIG. 44 covered by the feeder top;

FIG. 44B depicts an enlarged view of the exposed annular access barrierportion of FIG. 44;

FIG. 44C depicts an enlarged view of the annular access barrier portionof FIG. 44B being penetrated by a bird's bill;

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

With reference to FIGS. 1-4, access device 11 includes an annularhousing 13 and an barrier insert 15. Housing 13, which is made of aresilient material (such as silicone, neoprene, or urethane), includesan outer lip 17 and an inner lip 19 which are interconnected by anexterior annular groove 21. The width of the groove 21 is approximatelyequal to the thickness of feeder body 23 (of a typical nectar-type birdfeeder), whereby surfaces 25 and 27 are in engagement with feeder bodysurfaces 29 and 31. Housing 13 also includes an interior annular groove33 and a plurality of pie-shaped flaps 35¹, 35², and 35³ which arenaturally biased towards the closed position as illustrated in FIG. 2.Reduced section at 37 decreases the thickness of the material whereflaps 35¹, 35², and 35³ join housing 13 and, in effect, forms a hinge37, to permit the barrier flaps to be pushed inward by the force of ahummingbird's bill 39, as illustrated in FIG. 4. Finally, becausehummingbirds are extremely sensitive to any surface friction encounteredby their bill and, in fact, will not attempt to push barrier flaps 35¹,35², and 35³ aside if any surface friction is encountered (such as istypical of resilient materials), it is necessary that the exteriorsurface of the flaps 35¹, 35², and 35³, or barrier insert surface 15 beof low friction. This can be accomplished by using a speciallyformulated resilient material having low friction characteristics, usinga low friction coating, such as Teflon, to coat the panels 35¹, 35², and35³, or finally, providing barrier insert 15 with inside wall 43 formedof low friction material.

Barrier insert 15 is made of a low friction, pliable material and, inits free state has the shape of a thin walled, tapered, cylinder.Barrier insert 15 has a thickened lip 41 at the larger end, which lip isreceived in interior annular groove 33. The insert 15 is maintained inthe closed position by the pinching forces of the flaps 35¹, 35², and35³ in three locations, as best illustrated in FIG. 3, by the opposingedges of flaps 35¹ -35², 35² -35³, and 35³ -35¹.

Penetration of the nectar feeder barrier by the hummingbird bill 39 isillustrated in FIG. 4. Bill 39 passes through the device barrier bypushing the resilient flaps 35¹, 35², and 35³ downward. When the bill iswithdrawn, the barrier returns to the naturally closed position as shownin FIG. 3.

In FIGS. 5-9, a second embodiment of the restrictive access device isillustrated. Device 51 includes an annular housing 53 and barrier insert65. Housing 53, which is made of a resilient material, includes an outerlip 55 and an inner lip 59 which are interconnected by an exteriorannular groove 57. The width of the groove 57 is approximately equal tothe thickness of the feeder body 23. As shown in FIGS. 5 and 8, housing53 includes an interior annular groove 63 and a plurality of triangularshaped appendages 61 located immediately below. The interior annulargroove 63 is shaped to accept barrier insert 65. Barrier insert 65 iscomprised of an external ring 69 connected to a series of flaps 71through a reduced cross sectional area 67, which acts as an integralhinge. When barrier insert 65 is seated into the housing 53, theresilient appendages 61 contact the interior surfaces 75 of thetriangular flaps 71, biasing them to closure. Alignment of the insertflaps 71 and the supporting resilient appendages 61, is maintained by anode 79 on the insert ring, fitted into a slot 77 in the housing. Inorder to facilitate penetration of the hummingbird's bill 39, as seen inFIG. 9, the exterior surface 73 of the barrier insert flaps are made of,or coated, with a low friction material. When the birds bill 39 iswithdrawn from the barrier insert 65 , the insert returns to thenormally closed position as seen in FIG. 5.

Referencing FIGS. 10-12 there is shown a construction of the restrictiveaccess device 81 adapted to fit within a plastic flower cup 87, in placeof a conventional bee guard. Restrictive access device 81 functions asan insect barrier, identical to the device of FIG. 5, the onlydifference being the way it is mounted to the feeder. The resilienthousing 83 of the device 81 is configured in the form of a disk with avertically extending skirt 85, sized to form an interference fit withthe side walls 89 of the plastic flower cup 87 . Restrictive accessdevice 81 is attached, by pushing it into the plastic flower cup 87, asshown by arrow 90. The resulting assembly is shown in FIG. 12.

Referencing FIGS. 13-16 there is shown the restrictive access device 99constructed to fit the tube of an inverted-type nectar feeder.Restrictive access device 99 functions as a barrier to insectsidentically to the device of FIG. 5 (by incorporating barrier insert65), but is shaped to fit the feeder tube 107, and incorporates anintegral pressure relieving valve 103. Resilient housing 101 includes anextended skirt 105 that is sized to fit snugly over the feeder tube 107.Restrictive access device 99 incorporates an integral pressure relievingvalve 103 to reduce the dripping that typically occurs with invertedtype feeders. Dripping results due to rising ambient air temperaturesand the resultant expansion of the air in the space above the nectarreservoir (not shown). This expansion forces nectar from the feederreservoir, out through feeder tube 107. To relieve this pressure, abreather tube 109 extends from the air space above the nectar to anopening 111 in the housing 101. Breather tube 109 is interference fittedwith the opening 111, that connects to the outside air through anintegrally formed valve seat 117, and check ball 115, as seen in FIG.14. Under normal, reduced pressure conditions, check ball 115 maintainsan airtight seal on the valve seat 117. In times of increasing ambienttemperatures, positive pressure above the nectar reservoir, passesthrough the breather tube, lifting check ball 115 off the valve seat117, against gravity or very light spring 118, as seen in FIG. 15. Checkball 115 and spring 106 are retained in the housing 101 by pushing thempast the reduced diameter lip 119. A reduced diameter orifice opening113 is incorporated into the resilient housing 101, to allow forsufficient pressure to build above the nectar reservoir, to open thevalve 103, before significant dripping occurs. FIG. 16 shows a graphicsymbol 121 that is used to show the correct orientation of the device99, when gravity alone, is used, to seat the check ball 115.

The following described embodiments and constructions were developed tosimplify the manufacturability and the performance of the restrictiveaccess devices of the present invention.

Referencing FIGS. 17-20, restrictive access device 131, formed of asemi-rigid or resilient material, includes an outer flange 133 and innernodes 135 which are connected by a pair of semi-circular walls 137₁, and137₂. The height of walls 137₁, and 137₂ is approximately equal to thefeeder body 23 (of a typical nectar-type bird feeder). Restrictiveaccess device 131 is held in place when surface 139 of flange 133 andsurface 141 of nodes 135 are in engagement with feeder body surfaces 29and 31. The restrictive access device 131 is installed into the feederbody 23 by pushing the inner nodes 135 past the feeder body 23 opening142. The restrictive access device 131 includes an access opening 143and an internal seating surface 145 immediately beneath. As seen in FIG.18, prior to installing the restrictive access device 131 into thefeeder body 23, it is necessary to position the resilient barrier sheet147 on the underside of the restrictive access device 131. Once theassembly is snapped into the feeder body 23, barrier sheet 147 islocated on seating surface 145 directly below access opening 143 andbetween feeder body surface 29 and the restrictive access device surface139. Barrier sheet 147 is further located by the semi-circular walls137₁, and 137₂, due to it having complimentary semi-circular cutouts, asshown at 149₁, and 149₂ in FIG. 18A, each having a semi-circular surface150₁ and 150₂, which engage walls 137₁ and 137₂. Barrier sheet 147 iscut through at 151 to form flaps 153 and 155 that are in contact withthe seating surface 145, thereby forming an insect barrier beneath therestrictive access device opening 143. Barrier flaps 153 and 155 arepushed off the seating surface 145 by the penetration of the bird's bill39 as shown in FIG. 20. Barrier flaps 153 and 155, being formed of aresilient material, will return to the normally seated and closedposition when the bill 39 is withdrawn. The embodiment shown has twobarrier flaps 153 and 155, but could be configured to have from onlyone, to many of them. In the event that only one barrier flap is used,it would be possible to construct the restrictive access device with atapered interior orifice, the inside wall of the orifice acting as theseating surface for the outside edge of the barrier flap.

With reference to FIGS. 21-23, restrictive access device 161, which ismade of a resilient material (such as silicone, or urethane), includesan outer flange 163 and an inner lip 165 which are interconnected by anexterior annular groove 167. The width of the groove 167 isapproximately equal to the thickness of feeder body 23 (of a typicalnectar-type bird feeder), whereby surfaces 171 and 173 are in engagementwith feeder body surfaces 29 and 31. Restrictive access device 161includes a barrier structure consisting of a plurality oftriangular-shaped flaps 179¹, 179², 179³ that are in contact at theiredges, thereby forming an effective closure as shown in FIG. 21. Anoptional reduced cross section at 181 where flaps 179¹, 179², and 179³join the access device inner wall 183 forms an integral hinge 181. Thishinge 181 acts to reduce the force required for a bird's bill 39 topenetrate barrier flaps 179¹, 179², and 179³, as illustrated in FIG. 23.Finally, because birds, particularly hummingbirds, are extremelysensitive to any surface friction encountered by their bill and, infact, will not attempt to penetrate the barrier flaps 179¹, 179², and179³ if any appreciable surface friction is encountered (such as istypical of many resilient materials) it is necessary that the exteriorsurface of flaps 179¹, 179², and 179³ be of low surface friction. Thiscan be accomplished by using a unique or specially formulated resilientmaterial having low surface friction characteristics, or by using a lowfriction material, such as Teflon, to coat the exterior surfaces of theflaps 179¹, 179², and 179³.

With reference to FIGS. 24 and 25, restrictive access device 191 isconstructed from a semi-rigid material (such as nylon) and includes anouter lip 193 and nodes 195 which are interconnected by a segmentedinner wall 201 thus forming a segmented exterior annular groove 197. Thewidth of the groove 197 is approximately equal to the thickness of thefeeder body 23 (of a typical nectar type bird feeder) whereby surfaces199 and 200 are in engagement with feeder body surfaces 29 and 31. Innerwall 201 may incorporate material cutouts 203 to allow for the necessarydistortion of the nodes 195 to fit into the feeder body 23. Restrictiveaccess device 191 includes a barrier structure consisting of a series ofradially projecting filaments 205 which are in radial contact andthereby present an effective closure barrier, as shown in FIG. 24. Asseen in FIG. 25, filaments 205 may have a reduced cross-sectional areaas shown at 207 so as to be easily deflected by the penetration of abird's bill.

A differently constructed embodiment of the restrictive access device211 of the invention is shown in FIGS. 26 through 28. Restrictive accessdevice 211 is held in the feeder body 23 by the contact of the undersidesurface of device flange 213 and the bottom lip 215 with externalsurface 29 and internal surface 31, respectively. Restrictive accessdevice 211 has an undercut groove 217 within the device access opening219. Groove 217 is adapted to receive a filament-type barrier insert 221as shown in FIG. 26A and 27. Barrier insert 221 is constructed of amultitude of filaments or bristles 223, held in place by twisted wire225. Barrier insert 221 is configured in a ring, as shown in FIG. 26A,in order to dispose the filaments 223 radially towards the center of therestrictive access device 211. The barrier insert 221 is inserted intothe restrictive access device 211 by pushing it past the opening 219into the under-cut groove 217. Insertion of the barrier insert 221 actsto deflect the outer portions of all filaments 223 radically inward asillustrated in FIG. 27. Brush-type barrier insert 221 is held in placein restrictive access device 211 by the spring tension of the twistedwire 225, or the resilient compression of the device undercut groove217, or both. The restrictive access device 211 is shown beingpenetrated by a bird's bill in FIG. 28. In order for the filament-typebarrier to prevent insect entry, while still being relatively easy forfeeding bird's to penetrate, the bristles or filaments should benumerous and of small cross-sectional area.

The FIGS. 29 and 30 show a simplified filament-type restrictive accessdevice 231. This construction of the restrictive access device 231consists of little more than the filament-type barrier insert of theprior described embodiment. Restrictive access device 231 is attacheddirectly to the feeder body 23 with the retaining clips 233. The clips233 act to hold the device in place by contacting the feeder body 23internal surface 31 and external surface 29. The clips 233 are attachedto the device 231 by winding them between the twisted wire 235, formingthem from an integral loop of wire, or by spot welding them in place.Installation of restrictive access device 231 is easily accomplished bycompressing the ring formed by twisted wire 235 and allowing it to snapback with the retaining clips 233 engaging the feeder body 23. Thefilaments 237 are readily displaced by the penetration of a bird's bill.This construction of the filament-type barrier embodiment of therestrictive access device of the invention has an added advantage overthe prior embodiments because the array of filaments 237 extends bothover and away from the feeder opening. This extension of the bristles237 away from the opening, will discourage larger insects from gettingclose to the opening in feeder body 23. Further, the filaments of bothof the brush-type barrier embodiments can be cut with a relatively sharppoint, to further discourage insects from forcing their way into tofeeder.

It should be noted that although both of the filament type barrierembodiments described used a circular brush configuration, any filamenttype barrier configuration, if sufficiently dense, would functionadequately. Filaments may be made from nylon, polyester or naturalfiber. Referring to FIGS. 31-33, a fluted barrier structure embodimentof the present invention is shown. Restrictive access device 241includes an outer flange 243 and inner lip 245 which are interconnectedby an exterior annular grove 247. Outer flange 243 is connected to theinner lip 245 by the access device inner wall 253, and includes groove247 the width of which is approximately equal to that of the feeder body23 (of a typical nectar type bird feeder) whereby surfaces 249 and 251are in engagement with feeder body surfaces 29 and 31. Restrictiveaccess device 241 includes an access barrier 255 consisting of a flutedstructure which is biased to normally close the feeder orifice. Barrierstructure 255 consists of a series of interconnected flutes 257 comingtogether at 259 to form an expandable closure. FIGS. 31A and 31B showalternate fluted barrier configurations with fewer flutes. As shown inFIG. 33, the penetration of the fluted barrier structure 255 by a bird'sbill 39 causes flutes 257 to expand and separate at 259, thus allowingaccess to the nectar feeder contents. By virtue of being constructed ofa resilient material, barrier structure 255 will return to the normallyclosed position upon withdrawal of the bird's bill 39.

Referring to FIGS. 34-35B there is shown a restrictive access device 261of the present invention with a web type barrier, constructed from apliable material. Restrictive access device 261 is held in place overthe feeder opening in an identical manner as that previously describedfor the fluted type barrier shown in FIG. 32. The barrier structure 263of restrictive access device 261 is shaped as a single web or reed asshown in FIGS. 34 and 34A. Barrier structure 263 consists of a flexiblewall 265 being held in a closed or crimped position as seen at 267 bythe applied pressure of a resilient, constricting band 269. Constrictingband 269 may be integrally molded, adhesively bonded, or retained byother means, including being held by an increased cross sectional areaof the flexible wall 265 as shown at 271. Restrictive access device 261is shown in FIG. 35 being penetrated by a bird's bill 39. Thispenetration forces the barrier structure 263 to separate, pushingflexible wall 265 against the constricting band 269. As shown in FIG.35A, distortion of the constricting band 269 will allow access to thenectar feeder contents and return barrier structure 263 to its closedcondition upon withdrawal of the bird's bill 39. The primary advantageof this embodiment of the invention is that with the exception of theresilient constricting band 269, the device can be constructed from anextremely pliable and not by necessity resilient material. Thisembodiment of the restrictive access device would allow for an extremelylow surface friction resisting force upon bill insertion, and theprecise control, depending on the size and geometry of the resilientconstricting band 269, of the penetration forces required.

Referring to FIGS. 36 and 37, there is shown an adhesively mountedconstruction of the restrictive access device of the invention.Restrictive access device 281 is held in place on the feeder body 23 byan annular shaped adhesive disk 283. The adhesive disk 283 lying incontact between the underside, and possibly textured, surface 285 of therestrictive access device flange 287 and the outside surface 29 of thefeeder body 23 acts to hold the restrictive access device 281 in place.As in the prior described embodiments, insects are prevented fromgaining access to the feeder interior by the fluted barrier structure289, of similar construction to that illustrated in FIG. 31.

The adhesively mounted restrictive access device 281 would be readilyadaptable to any embodiment previously described in this specification.The restrictive access device 281 could be provided with the adhesivedisk 283 attached or provided as a separate piece. In either instance,the exposed surfaces of the adhesive would be protected with a peel awaybacking. The primary application of this adhesively mounted device,would be for feeders with smaller type feeding openings that are nottypically defined by any floral shaped insert.

Referring to FIGS. 38-40, there is shown a gravitationally biasedbarrier embodiment of the restrictive access device of the invention. Asseen in FIG. 39B, restrictive access device 301 is secured to the feederbody 23 by the contact of the underside 302 of the flange 303 and theupper surface 305 of the node 307 with the feeder body 23 surfaces 29and 31 respectively. Restrictive access device 301 is snapped into thefeeder body 23 in a similar manner to the device shown in FIG. 17.Restrictive access device 301 has a gravitationally biased barrier,consisting of a pair of counter weighted gates 309 located immediatelybelow the device access orifice 311. Gates 309 are designed to rotatefreely at hinge pins 313, that are interference fitted in the insidewalls of the semi-circular structures 315₁ and 315₂. Gates 309 aregravitationally biased to remain closed as seen at 317 in FIG. 39, byvirtue of having a greater mass on the pivot-side opposite the deviceaccess orifice 311. In order that the two gates present an effectivebarrier as seen at 317, it is necessary that they contact or nearlycontact the underside of access orifice 311, as seen at 319.

As seen in FIG. 40, counter-weighted barrier gates 309 are easilydisplaced by the penetration of a bird's bill 39. An advantage of thiscounter-weighted barrier embodiment is that the amount of force requiredfor penetration is easily controlled by the balance of mass of the gatesrelative to the pivot-point.

Referring to FIGS. 41 and 42, there is shown another restrictive accessdevice of the invention, constructed to fit on an inverted type tubefeeder. Restrictive access device 331 has a flexible annular skirt 333adapted to fit over end 337 of feeder tube 335. The barrier structure339 of restrictive access device 331 can be in the form of anyembodiment previously described in this specification.

Referring to FIGS. 43-44C, there is shown an embodiment of therestrictive access device of the invention 351, built integrally withinthe lid 353 of a typical saucer type nectar feeder. This feeder 351 hasa lid 353 provided with a series of circumferential cutouts 355₁ -355₆which expose annular shaped barrier structure 357. Annular shapedbarrier structure 357 is formed by the contact of an inside wiper 359and outside wiper 361, as seen in FIG. 44B. These wipers 359 and 361,being formed of a resilient material, come together to form an effectivebarrier closure as seen at 363. In order to ensure uniform alignmentbetween the inside and outside wipers 359 and 361, annular barrierstructure 357 is of unitary construction as shown at 365 in FIG. 44A.The points 365 where the inside and outside wipers 359 and 361 areintegral, will be located opposite the feeder lid 353 circumferentialcutouts 355₁₋₆, in order not to be accessible to the feeding bird'sbill. Annular shaped barrier structure 357 may be attached to the feederlid 353 by providing increased sections 367₁, and 367₂, adapted to beinterference fitted to annular grooves 369₁, and 369₂ in the feeder lid353. The annular shaped barrier structure may be attached to the feederlid 353 by other means including, but not limited to, a self adhesiveattachment as previously described in this specification. It may proveto be desirable that the attachment means allow for some radialcompression of annular barrier structure 357 to allow the inside andoutside and outside wipers 359 and 361 to be forced into contact asshown at 363, in FIG. 44B. Annular barrier structure 357 is easilypenetrated by a bird's bill 39 as seen in FIG. 44C, and will return tothe normally closed position, as seen in FIG. 44B, upon withdrawal ofthe bird's bill.

Virtually any of the prior described restrictive access devices could beconstructed in order to fit a specially adapted saucer feeder lid.

Lastly, it should be noted that the opening required for hummingbirds tofeed is quite small, down to approximately 1/16" across. This very smallopening is sufficient in size, as these birds feed by lapping the nectarwith their tongues. All of the appended figures show an exaggeratedrelative size of the barrier structures, and in those showing billpenetration, greatly exaggerate the degree of penetration. This was doneto more clearly illustrate the structures and functioning of the variousbarrier embodiments.

Others may practice this invention in any of the numerous ways whichwill be suggested to one skilled in the art upon reading thisdisclosure. All such practice of the invention is considered to becovered hereby provided it falls within the scope of the appendedclaims.

I claim:
 1. A restrictive access device for mounting at a feeder openingof a nectar type bird feeder, said access device including:a. a barrierwhich, when said barrier is installed at said feeder opening, is in afirst position which closes said feeder opening sufficiently to preventinsects from passing through said feeder opening, said barrier beingmovable to a second position by the pressure of a bird's bill to permitnectar feeding, said barrier returning to substantially said firstposition when said bill is withdrawn; and b. means to position saidaccess device adjacent to said feeder opening, thereby positioning saidbarrier at said feeder opening when said barrier is in said firstposition.
 2. The restrictive access device of claim 1, wherein saidaccess device includes an annulus having a center axis, and wherein saidbarrier includes a normally closed rosette of triangular flaps, each ofsaid flaps having a base edge, two side edges and an apex, each saidbase edge connected to said annulus, each said side edge normallyengaging said side edge of an adjacent flap when said rosette is closed,said apexes being at, approximately, said center axis of said annuluswhen said rosette is closed, said flaps being adapted to move to saidsecond position with said apexes separating to open said rosette when abird's bill is thrust therein.
 3. The restrictive access device of claim2, wherein said triangular flaps are internally biased to said firstposition to form said normally closed rosette.
 4. The restrictive accessdevice of claim 2, wherein said access device includes means, separatefrom said flaps, for biasing said flaps to said first position to formsaid normally closed rosette.
 5. The restrictive access device of claim2, wherein said triangular flaps are formed integrally with saidannulus.
 6. The restrictive access device of claim 1, wherein saidbarrier consists of a plurality of flexible filaments and means forholding said filaments in a predetermined pattern.
 7. The restrictiveaccess device of claim 6, wherein each of said filaments has a first andsecond end, and said means for holding said filaments is in the form ofa loop, at least a portion of said first ends projecting into theinterior space defined by said loop.
 8. The restrictive access device ofclaim 7, wherein said positioning means is a plurality of clips securedto said filament holding means.
 9. The restrictive access device ofclaim 7, wherein said access device includes an annulus, said annulusincluding said positioning means, said annulus further including meansto hold said barrier adjacent to said filament holding means.
 10. Therestrictive access device of claim 1, wherein said restrictive accessincludes an annulus, said annulus including said positioning means, saidannulus further including a seating surface, and wherein said barrier isat least one flap, normally biased into contact with said seatingsurface of said annulus and adopted to swing to said second position inresponse to pressure from a bird's bill.
 11. The restrictive accessdevice of claim 1, wherein said restrictive access includes an annulus,said annulus including said positioning means, said annulus furtherincluding an opening, and wherein said barrier is at least one gateconnected to said annulus, said gate normally being held in said firstposition by gravitational force to close said annulus opening, said gatebeing movable to said second position in response to pressure from abird's bill.
 12. The restrictive access device of claim 1, wherein saidbarrier is formed of a fluted resilient material, said fluted resilientmaterial having a normally closed opening in the center thereof throughwhich a bird's bill may be projected and which, by virtue of beingformed of resilient material, is biased to return to said closedposition when the bird's bill is withdrawn.
 13. The restrictive accessdevice of claim 12, wherein said fluted resilient material is a singlepiece of material.
 14. The restrictive access device of claim 13,wherein said restrictive access device includes an annulus, said annulusincluding said positioning means, and wherein said fluted resilientmaterial is formed integrally with said annulus.
 15. The restrictiveaccess device of claim 1, wherein said barrier is formed of a web ofpliable material having an opening therein, said restrictive accessdevice including a biasing means secured to said web adjacent to saidweb opening to normally close said web opening, said biasing meansyielding to permit said web adjacent to said web opening to move to saidsecond position in response to pressure from a bird's bill.
 16. Therestrictive access device of claim 15, wherein said restrictive accessdevice includes an annulus, said annulus including said positioningmeans, and wherein said web is formed integrally with said annulus. 17.The restrictive access device of claim 1, wherein said restrictiveaccess device includes a cylindrical skirt portion, said skirt portionhaving an exterior surface adapted to fit with a conventional bee guardtype feeder opening.
 18. The restrictive access device of claim 1,wherein said restrictive access device includes a support surface, andwherein said positioning means includes a contact adhesive secured tosaid support surface and covered by a protective backing to be removedimmediately prior to installation of said restrictive access device. 19.The restrictive access device of claim 1, wherein said means to positionsaid barrier over said opening includes means to secure said restrictiveaccess device to the feeding end of a conventional inverted-type feedertube.
 20. The restrictive access device of claim 19, wherein saidpositioning means includes a means for relieving pressure over aninverted-type feeder food reservoir.
 21. The restrictive access deviceof claim 20, wherein said restrictive access device further includes abreather tube adapted to extend to the air space over an inverted-typefeeder food reservoir.
 22. The restrictive access device of claim 21,wherein said restrictive access device includes a pressure relievingvalve connected to said breathing tube.
 23. The restrictive accessdevice of claim 22, wherein said pressure relieving valve includes acheck ball and an integral valve seat formed in said positioning means.24. A nectar type bird feeder, said bird feeder including:a. a housingfor holding nectar, said housing including at least one feeder opening;and b. a barrier, said barrier being installed at said feeder opening,said barrier having a first position which closes said feeder openingsufficiently to prevent insects from passing through feeder opening,said barrier being movable to a second position by the pressure of abird's bill to permit nectar feeding, said barrier returning tosubstantially said first position when said bill is withdrawn.
 25. Therestrictive access device of claim 24, wherein each said feeder openingis elongated in form and wherein said barrier comprises a pair offlexible wipers coming together at said feeder opening.